Pages

Extreme Place on Earth

January 18, 2008

ATACAMA DESERT(The Driest Place)

You'd be Surprised to Find...

The Atacama desert is nestled along the coast of Chile, South America - right next to the Pacific Ocean - the biggest body of water in the world. Much of the desert extends up into the Andes mountains and is very high in elevation. Unlike more familiar deserts, like the Sahara desert in Africa and the Mojave in California, the Atacama is actually a pretty cold place, with average daily temperatures ranging between 0°C and 25°C. The annual rainfall (or lack of it) defines a desert, but that doesn't mean that it never rains in Atacama. Every so often a warming effect over the Pacific Ocean around the equator changes the weather the world over and even places like the driest desert in the world can become doused with drenching storms. Even though Atacama gets almost no rainfall, water is still present in this arid place.

Does Anything Live There?

Many people have the view that deserts are places forsaken by Mother Nature and that no living thing would possibly want to set up camp in a place so dry. Although it is tough to find anything living in the Atacama there are isolated pockets and small patches of plants, which support life for animals and insects. Some plant species have adapted well to this dry environment by developing tap roots that run very deep into the ground gathering water from below. There are flocks of flamingos that live in and around the salt lakes feeding on red algae that grows in the waters. There are even people living in the Atacama.

There is a town called Calama in the desert which is complete with motels, restaurants and shops, but it is definitely not the norm. For the most part, Atacama is a pretty lonely place. Humans have lived in the Atacama for many thousands of years, based on the cultural relics and artifacts that archeaologists have found. The South American Indians who have set up housekeeping in the desert over the millenia have left relics from their culture and even themselves. Because the Atacama is so bone-dry the bodies of the buried indians have dried perfectly preserved turning them into mummies. Some of the oldest mummies found anywhere on earth have come from the Atacama Desert and have been dated to be 9,000 years old!

What Causes Deserts?

One reason is that the high atmospheric pressure in this region over the Andes can cause dry, cold air from the upper altitudes to compress and come down to earth. This dry air has almost no water vapor so it can be easily heated by the sun, causing high ground temperatures with very low humidity.